Commit Graph

8454 Commits

Author SHA1 Message Date
Craig Topper
35189d5221 [SelectionDAG] Make ISD::isConstantSplatVector always return an element sized APInt.
This partially reverts r311429 in favor of making ISD::isConstantSplatVector do something not confusing. Turns out the only other user of it was also having to deal with the weird property of it returning a smaller size.

So rather than continue to deal with this quirk everywhere, just make the interface do something sane.

Differential Revision: https://reviews.llvm.org/D37039

llvm-svn: 311510
2017-08-22 23:54:13 +00:00
Jonas Devlieghere
a680a8f5f8 [Debug info] Add new DbgValues after looping over DAG
I was contacted by Jesper Antonsson from Ericsson who ran into problems
with r311181 in their test suites with for an out-of-tree target.
Because of the latter I don't have a reproducer, but we definitely don't
want to modify the data structure on which we are iterating inside the
loop.

llvm-svn: 311466
2017-08-22 16:28:07 +00:00
Renato Golin
c070c73d5e [ARM] Avoid creating duplicate ANDs in SelectionDAG
When expanding a BRCOND into a BR_CC, do not create an AND 1
if one already exists.

Review: D36705

Patch by Joel Galenson <jgalenson@google.com>

llvm-svn: 311447
2017-08-22 11:02:45 +00:00
Sjoerd Meijer
e0c933f5d6 [SelectionDAG] Add getNode debug messages
This adds debug messages to various functions that create new SDValue nodes.
This is e.g. useful to have during legalization, as otherwise it can prints
legalization info of nodes that did not appear in the dumps before.

Differential Revision: https://reviews.llvm.org/D36984

llvm-svn: 311444
2017-08-22 10:43:51 +00:00
Craig Topper
b49f0893b2 [X86] Prevent several calls to ISD::isConstantSplatVector from returning a narrower APInt than the original scalar type
ISD::isConstantSplatVector can shrink to the smallest splat width. But we don't check the size of the resulting APInt at all. This can cause us to misinterpret the results.

This patch just adds a flag to prevent the APInt from changing width.

Fixes PR34271.

Differential Revision: https://reviews.llvm.org/D36996

llvm-svn: 311429
2017-08-22 05:40:17 +00:00
Benjamin Kramer
49a49fe816 Move helper classes into anonymous namespaces.
No functionality change intended.

llvm-svn: 311288
2017-08-20 13:03:48 +00:00
Jatin Bhateja
6b4c205685 [DAGCombiner] Extending pattern detection for vector shuffle.
Summary:
    If all the operands of a BUILD_VECTOR extract elements from same vector then split the
    vector efficiently based on the maximum vector access index.

    Reviewers: zvi, delena, RKSimon, thakis

    Reviewed By: RKSimon

    Subscribers: chandlerc, eladcohen, llvm-commits

    Differential Revision: https://reviews.llvm.org/D35788

llvm-svn: 311255
2017-08-19 18:08:59 +00:00
Jatin Bhateja
66f7958e91 Revert rL311247 : To rectify commit message.
Summary: This reverts commit rL311247.

Differential Revision: https://reviews.llvm.org/D36927

llvm-svn: 311252
2017-08-19 17:59:58 +00:00
Jatin Bhateja
6f0d0d23b0 Merge branch 'arcpatch-D35788'
llvm-svn: 311247
2017-08-19 17:00:04 +00:00
Jatin Bhateja
1c56863739 Revert rL311242 "Extension of shuffle vector pattern detection, updating post rebase."
Summary:

This reverts commit rL311242.

Differential Revision: https://reviews.llvm.org/D36924

llvm-svn: 311246
2017-08-19 16:40:06 +00:00
Jatin Bhateja
313f97dd84 Extension of shuffle vector pattern detection, updating post rebase.
llvm-svn: 311242
2017-08-19 15:58:36 +00:00
Jonas Devlieghere
e101b07a1d [Debug info] Transfer DI to fragment expressions for split integer values.
This patch teaches the SDag type legalizer how to split up debug info for
integer values that are split into a hi and lo part.

(re-commit)

Differential Revision: https://reviews.llvm.org/D36805

llvm-svn: 311181
2017-08-18 18:07:00 +00:00
Craig Topper
e3edd9c9be [DAGCombiner] Fix bad comment that had immediate values swapped from the code and what they need to be to make sense. NFC
llvm-svn: 311144
2017-08-18 04:52:46 +00:00
Jonas Devlieghere
30756da212 Revert "[Debug info] Transfer DI to fragment expressions for split integer values."
This reverts commit r311102.

llvm-svn: 311111
2017-08-17 17:58:33 +00:00
Jonas Devlieghere
622fedc001 [Debug info] Transfer DI to fragment expressions for split integer values.
This patch teaches the SDag type legalizer how to split up debug info for
integer values that are split into a hi and lo part.

Differential Revision: https://reviews.llvm.org/D36805

llvm-svn: 311102
2017-08-17 17:06:48 +00:00
Adrian Prantl
6a57daad81 Improve line debug info when translating a CaseBlock to SDNodes.
The SelectionDAGBuilder translates various conditional branches into
CaseBlocks which are then translated into SDNodes. If a conditional
branch results in multiple CaseBlocks only the first CaseBlock is
translated into SDNodes immediately, the rest of the CaseBlocks are
put in a queue and processed when all LLVM IR instructions in the
basic block have been processed.

When a CaseBlock is transformed into SDNodes the SelectionDAGBuilder
is queried for the current LLVM IR instruction and the resulting
SDNodes are annotated with the debug info of the current
instruction (if it exists and has debug metadata).

When the deferred CaseBlocks are processed, the SelectionDAGBuilder
does not have a current LLVM IR instruction, and the resulting SDNodes
will not have any debuginfo. As DwarfDebug::beginInstruction() outputs
a .loc directive for the first instruction in a labeled
block (typically the case for something coming from a CaseBlock) this
tends to produce a line-0 directive.

This patch changes the handling of CaseBlocks to store the current
instruction's debug info into the CaseBlock when it is created (and the
SelectionDAGBuilder knows the current instruction) and to always use
the stored debug info when translating a CaseBlock to SDNodes.

Patch by Frej Drejhammar!

Differential Revision: https://reviews.llvm.org/D36671

llvm-svn: 311097
2017-08-17 16:57:13 +00:00
Simon Pilgrim
8be9f4af4f [DAGCombiner] Add support for non-uniform constant vectors to (mul x, (1 << c)) -> x << c
llvm-svn: 311083
2017-08-17 13:03:34 +00:00
Elad Cohen
124d32829c [SelectionDAG] Teach the vector-types operand scalarizer about SETCC
When v1i1 is legal (e.g. AVX512) the legalizer can reach
a case where a v1i1 SETCC with an illgeal vector type operand
wasn't scalarized (since v1i1 is legal) but its operands does
have to be scalarized. This used to assert because SETCC was
missing from the vector operand scalarizer.

This patch attemps to teach the legalizer to handle these cases
by scalazring the operands, converting the node into a scalar
SETCC node.

Differential revision: https://reviews.llvm.org/D36651

llvm-svn: 311071
2017-08-17 08:06:36 +00:00
Andrew Kaylor
53a5fbb45f Add strictfp attribute to prevent unwanted optimizations of libm calls
Differential Revision: https://reviews.llvm.org/D34163

llvm-svn: 310885
2017-08-14 21:15:13 +00:00
Amaury Sechet
9c529b6be3 [DAGCombine] Do not try to deduplicate commutative operations if both operand are the same.
Summary: It is creating useless work as the commuted nodes is the same as the node we are working on in that case.

Reviewers: jyknight, nemanjai, mkuper, spatel, RKSimon, zvi, bkramer

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D33840

llvm-svn: 310832
2017-08-14 11:44:03 +00:00
Elad Cohen
6a9edda356 [SelectionDAG] combine vextract (v1iX extract_subvector(vNiX, Idx))
into vextract(vNiX,Idx) when creating vextract with getNode().
This case appeared in AVX512 after fixing pr33349 in r310552.

Differential revision: https://reviews.llvm.org/D36571

llvm-svn: 310828
2017-08-14 10:49:45 +00:00
Elad Cohen
3a90a0c10d Revert "[DAGCombiner] Extending pattern detection for vector shuffle (REAPPLIED)"
This reverts commit r310782.

llvm-svn: 310822
2017-08-14 09:06:00 +00:00
Craig Topper
2251ef95a3 [X86][ARM][TargetLowering] Add SrcVT to isExtractSubvectorCheap
Summary:
Without the SrcVT its hard to know what is really being asked for. For example if your target has 128, 256, and 512 bit vectors. Maybe extracting 128 from 256 is cheap, but maybe extracting 128 from 512 is not.

For x86 we do support extracting a quarter of a 512-bit register. But for i1 vectors we don't have isel patterns for extracting arbitrary pieces. So we need this to have a correct implementation of isExtractSubvectorCheap for mask vectors.

Reviewers: RKSimon, zvi, efriedma

Reviewed By: RKSimon

Subscribers: aemerson, javed.absar, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D36649

llvm-svn: 310793
2017-08-13 17:29:07 +00:00
Simon Pilgrim
5a86f0e717 [DAGCombiner] Extending pattern detection for vector shuffle (REAPPLIED)
If all the operands of a BUILD_VECTOR extract elements from same vector then split the vector efficiently based on the maximum vector access index.

Reapplied with fix to only work with simple value types.

Committed on behalf of @jbhateja (Jatin Bhateja)

Differential Revision: https://reviews.llvm.org/D35788

llvm-svn: 310782
2017-08-12 17:43:25 +00:00
Sanjay Patel
169dae70a6 [x86] use more shift or LEA for select-of-constants (2nd try)
The previous rev (r310208) failed to account for overflow when subtracting the
constants to see if they're suitable for shift/lea. This version add a check
for that and more test were added in r310490.

We can convert any select-of-constants to math ops:
http://rise4fun.com/Alive/d7d

For this patch, I'm enhancing an existing x86 transform that uses fake multiplies
(they always become shl/lea) to avoid cmov or branching. The current code misses
cases where we have a negative constant and a positive constant, so this is just
trying to plug that hole.

The DAGCombiner diff prevents us from hitting a terrible inefficiency: we can start
with a select in IR, create a select DAG node, convert it into a sext, convert it
back into a select, and then lower it to sext machine code.

Some notes about the test diffs:

1. 2010-08-04-MaskedSignedCompare.ll - We were creating control flow that didn't exist in the IR.
2. memcmp.ll - Choose -1 or 1 is the case that got me looking at this again. We could avoid the 
   push/pop in some cases if we used 'movzbl %al' instead of an xor on a different reg? That's a 
   post-DAG problem though.
3. mul-constant-result.ll - The trade-off between sbb+not vs. setne+neg could be addressed if
   that's a regression, but those would always be nearly equivalent.
4. pr22338.ll and sext-i1.ll - These tests have undef operands, so we don't actually care about these diffs.
5. sbb.ll - This shows a win for what is likely a common case: choose -1 or 0.
6. select.ll - There's another borderline case here: cmp+sbb+or vs. test+set+lea? Also, sbb+not vs. setae+neg shows up again.
7. select_const.ll - These are motivating cases for the enhancement; replace cmov with cheaper ops.

Assembly differences between movzbl and xor to avoid a partial reg stall are caused later by the X86 Fixup SetCC pass.

Differential Revision: https://reviews.llvm.org/D35340

llvm-svn: 310717
2017-08-11 15:44:14 +00:00
Nirav Dave
0a48e5d506 Improve handling of insert_subvector of bitcast values
Fix insert_subvector / extract_subvector merges of bitcast values.

Reviewers: efriedma, craig.topper, RKSimon

Subscribers: RKSimon, llvm-commits

Differential Revision: https://reviews.llvm.org/D34571

llvm-svn: 310711
2017-08-11 13:21:41 +00:00
Nirav Dave
d1b3f09faa [X86][DAG] Switch X86 Target to post-legalized store merge
Move store merge to happen after intrinsic lowering to allow lowered
stores to be merged.

Some regressions due in MergeConsecutiveStores to missing
insert_subvector that are addressed in follow up patch.

Reviewers: craig.topper, efriedma, RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D34559

llvm-svn: 310710
2017-08-11 13:21:35 +00:00
Simon Pilgrim
83cf3a29b5 [DAGCombiner] Remove shuffle support from simplifyShuffleMask
rL310372 enabled simplifyShuffleMask to support undef shuffle mask inputs, but its causing hangs.

Removing support until I can triage the problem

llvm-svn: 310699
2017-08-11 08:37:00 +00:00
Nirav Dave
f8556ad48f Revert "[DAG] Cleanup unused nodes after store merge. NFCI."
This reverts commit r310648 which causes an unexpected assertion failure

llvm-svn: 310659
2017-08-10 21:03:36 +00:00
Nirav Dave
4d28c0ff4f [DAG] Relax type restriction for store merge
Summary: Allow stores of bitcastable types to be merged by peeking through BITCAST nodes and recasting stored values constant and vector extract nodes as necessary.

Reviewers: jyknight, hfinkel, efriedma, RKSimon, spatel

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D34569

llvm-svn: 310655
2017-08-10 19:52:45 +00:00
Nirav Dave
99d9d24553 [DAG] Cleanup unused nodes after store merge. NFCI.
llvm-svn: 310648
2017-08-10 18:53:14 +00:00
Nirav Dave
06242a99ce [DAG] Rewrite expression. NFC.
llvm-svn: 310608
2017-08-10 15:29:33 +00:00
Nirav Dave
926e2d39bf [X86] Keep dependencies when constructing loads in combineStore
Summary:
Preserve chain dependecies between old and new loads constructed to
prevent loads from reordering below later stores.

Fixes PR34088.

Reviewers: craig.topper, spatel, RKSimon, efriedma

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D36528

llvm-svn: 310604
2017-08-10 15:12:32 +00:00
Guy Blank
136b543745 [SelectionDAG] Allow constant folding for implicitly truncating BUILD_VECTOR nodes.
In FoldConstantArithmetic, handle BUILD_VECTOR nodes that do implicit truncation on the elements.

This is similar to what is done in FoldConstantVectorArithmetic.

Differential Revision:
https://reviews.llvm.org/D36506

llvm-svn: 310593
2017-08-10 14:09:50 +00:00
Elad Cohen
22ba97a0a6 [SelectionDAG] When scalarizing vselect, don't assert on
a legal cond operand.

When scalarizing the result of a vselect, the legalizer currently expects
to already have scalarized the operands. While this is true for the true/false
operands (which have the same type as the result), it is not case for the
condition operand. On X86 AVX512, v1i1 is legal - this leads to operations such
as '< N x type> vselect < N x i1> < N x type> < N x type>' where < N x type > is
illegal to hit an assertion during the scalarization.

The handling is similar to r205625.
This also exposes the fact that (v1i1 extract_subvector) should be legal
and selectable on AVX512 - We do this by custom lowering to vector_extract_elt.
This still leaves us in some cases with redundant dag nodes which will be
combined in a separate soon to come patch.

This fixes pr33349.

Differential revision: https://reviews.llvm.org/D36511

llvm-svn: 310552
2017-08-10 07:44:23 +00:00
David Blaikie
76fb649b0d Reduce variable scope by moving declaration into if clause
llvm-svn: 310506
2017-08-09 18:34:18 +00:00
Nirav Dave
6110d3ad00 [DAG] Explicitly cleanup merged load values during store merge. NFCI.
llvm-svn: 310474
2017-08-09 13:37:07 +00:00
Nirav Dave
8a813cf646 [DAG] Introduce peekThroughBitcast function. NFCI.
llvm-svn: 310405
2017-08-08 20:01:18 +00:00
Nirav Dave
515116d7c2 [DAG] Update comments. NFC.
llvm-svn: 310404
2017-08-08 19:52:19 +00:00
Simon Pilgrim
91b7b991d4 [DAGCombiner] simplifyShuffleMask - handle UNDEF inputs from shuffles as well as BUILD_VECTOR
Minor extension to D36393

llvm-svn: 310372
2017-08-08 16:10:33 +00:00
Simon Pilgrim
ef44228acb [DAGCombiner] Simplify shuffle mask index if the referenced input element is UNDEF
Fixes one of the cases in PR34041.

Differential Revision: https://reviews.llvm.org/D36393

llvm-svn: 310344
2017-08-08 11:03:30 +00:00
Sanjay Patel
807f92b8ff [x86] revert r310208 to investigate test-suite failures (PR34105 / PR34097)
llvm-svn: 310264
2017-08-07 15:47:48 +00:00
Nirav Dave
3d3bde7682 [DAG] Extend visitSCALAR_TO_VECTOR optimization to truncated vector.
Relanding after case to insert explicit truncation as necessary.

Allow SCALAR_TO_VECTOR of EXTRACT_VECTOR_ELT to reduce to
EXTRACT_SUBVECTOR of vector shuffle when output is smaller. Marginally
improves vector shuffle computations.

Reviewers: efriedma, RKSimon, spatel

Subscribers: javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D35566

llvm-svn: 310256
2017-08-07 14:07:49 +00:00
Guy Blank
5ca01695f7 [SelectionDAG] reset NewNodesMustHaveLegalTypes flag between basic blocks
The NewNodesMustHaveLegalTypes flag is set to false at the beginning of CodeGenAndEmitDAG, and set to true after legalizing types.
But before calling CodeGenAndEmitDAG we build the DAG for the basic block.
So for the first basic block NewNodesMustHaveLegalTypes would be 'false' during the SDAG building, and for all other basic blocks it would be 'true'.

This patch sets the flag to false before SDAG building each basic block.

Differential Revision:
https://reviews.llvm.org/D33435

llvm-svn: 310239
2017-08-07 05:51:14 +00:00
Sanjay Patel
a923c2ee95 [x86] use more shift or LEA for select-of-constants
We can convert any select-of-constants to math ops:
http://rise4fun.com/Alive/d7d

For this patch, I'm enhancing an existing x86 transform that uses fake multiplies 
(they always become shl/lea) to avoid cmov or branching. The current code misses 
cases where we have a negative constant and a positive constant, so this is just 
trying to plug that hole.

The DAGCombiner diff prevents us from hitting a terrible inefficiency: we can start 
with a select in IR, create a select DAG node, convert it into a sext, convert it 
back into a select, and then lower it to sext machine code.

Some notes about the test diffs:

1. 2010-08-04-MaskedSignedCompare.ll - We were creating control flow that didn't exist in the IR.
2. memcmp.ll - Choose -1 or 1 is the case that got me looking at this again. I 
   think we could avoid the push/pop in some cases if we used 'movzbl %al' instead of an xor on 
   a different reg? That's a post-DAG problem though.
3. mul-constant-result.ll - The trade-off between sbb+not vs. setne+neg could be addressed if 
   that's a regression, but I think those would always be nearly equivalent.
4. pr22338.ll and sext-i1.ll - These tests have undef operands, so I don't think we actually care about these diffs.
5. sbb.ll - This shows a win for what I think is a common case: choose -1 or 0.
6. select.ll - There's another borderline case here: cmp+sbb+or vs. test+set+lea? Also, sbb+not vs. setae+neg shows up again.
7. select_const.ll - These are motivating cases for the enhancement; replace cmov with cheaper ops.

Assembly differences between movzbl and xor to avoid a partial reg stall are caused later by the X86 Fixup SetCC pass.

Differential Revision: https://reviews.llvm.org/D35340

llvm-svn: 310208
2017-08-06 16:27:07 +00:00
Nico Weber
b24df62bb6 Revert r310058, it caused PR34073.
llvm-svn: 310118
2017-08-04 20:24:13 +00:00
Simon Pilgrim
5c63586489 [DAGCombiner] Extending pattern detection for vector shuffle.
If all the operands of a BUILD_VECTOR extract elements from same vector then split the vector efficiently based on the maximum vector access index.

Committed on behalf of @jbhateja (Jatin Bhateja)

Differential Revision: https://reviews.llvm.org/D35788

llvm-svn: 310058
2017-08-04 12:46:35 +00:00
Matt Arsenault
a52391f2db DAG: Provide access to Pass instance from SelectionDAG
This allows accessing an analysis pass during lowering.

llvm-svn: 309991
2017-08-03 21:54:00 +00:00
Nirav Dave
3fc1c2365c [DAG] Allow merging of stores of vector loads
Remove restriction disallowing merging of stores vector loads into
larger store of larger vector load.

Reviewers: RKSimon, efriedma, spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D36158

llvm-svn: 309951
2017-08-03 15:51:20 +00:00
Nirav Dave
e44032f7e7 [DAG] Improve candidate pruning in store merge failure case. NFCI
During store merge we construct a sorted list of consecutive store
candidates and consider subsequences for merging into a single
store. For each subsequence we check if the stored value type is legal
the merged store would have valid and fast and if the constructed
value to be stored is valid. The only properties that affect this
check between subsequences is the size of the subsequence, the
alignment of the first store, the alignment of the stored load value
(when merging stores-of-loads), and whether the merged value is a
constant zero.

If we do not find a viable mergeable subsequence starting from the
first store of length N, we know that a subsequence starting at a
later store of length N will also fail unless the new store's
alignment, the new load's alignment (if we're merging store-of-loads),
or we've dropped stores of nonzero value and could construct a merged
stores of zero (for merging constants).

As a result if we fail to find a valid subsequence starting from the
first store we can safely skip considering subsequences that start
with subsequent stores unless one of the above properties is
true. This significantly (2x) improves compile time in some
pathological cases.

Reviewers: RKSimon, efriedma, zvi, spatel, waltl

Subscribers: grandinj, llvm-commits

Differential Revision: https://reviews.llvm.org/D35901

llvm-svn: 309830
2017-08-02 16:35:58 +00:00